C0310

DTC C0310 Motor A/B Circuit Open






Circuit Description

The transfer case encoder motor is a permanent magnet DC motor and gear reduction assembly. The encoder motor is controlled with a pulse width modulated (PWM) circuit within the transfer case shift control module. This circuit consists of a power supply relay (Motor Feed A) circuit that supplies voltage to the motor. The Motor Control B circuit is a PWM driver that varies the duty cycle to control the amount of current through the motor to ground.

This DTC detects an open on the Motor Feed A circuit or the Motor Control B circuit.

Conditions for Setting the DTC

- The system will test the motor circuits by checking for unwanted voltage.
- The system supplies voltage on the Motor A circuit and reads the voltage back on the Motor B circuit.
- The transfer case shift control module senses no voltage return on the Motor Feed A circuit or the Motor Control B circuit.
- If the system detects a problem with the circuits, the DTC is logged.

Action Taken When the DTC Sets

All clutch activation (slip control) will be disabled. The SERVICE indicator (AWD/4WD) lamp will be latched ON for the remainder of the current ignition cycle.

Conditions for Clearing the DTC

- The transfer case shift control module will clear the DTC if the condition for setting the DTC no longer exists.
- A history DTC will clear after 100 consecutive ignition cycles without a fault present.
- History DTCs can be cleared using a scan tool.

Test Description

The numbers below refer to the step numbers on the diagnostic table.

2. Tests the motor circuit for a current malfunction.
3. Tests Motor Feed A for an open circuit.
4. Tests Motor Control B for an open circuit.
5. Tests for an open across the motor windings.